A preparation method of a cathode material for a secondary battery is provided. First, a lithium metal phosphate material and a first conductive carbon are provided. The lithium metal phosphate material is made of a plurality of secondary particles. Each of the secondary particles is formed by the aggregation of a plurality of primary particles. An interparticle space is formed between the plurality of primary particles. Next, the lithium metal phosphate material and the first conductive carbon are mixed by a mechanical method, and a composite material is prepared. The first conductive carbon is uniformly arranged in the interparticle space. After that, a second conductive carbon, a binder and a solvent are provided. Finally, the composite material, the second conductive carbon, the binder and the solvent are mixed, and a cathode material for preparing a positive plate is prepared.

The present disclosure provides core-shell nickel ferrite, a nickel ferrite@C material and preparation methods and application thereof. The preparation method of the core-shell nickel ferrite includes: preparing nickel iron glycerate ball powder by a solvothermal method; and under an air condition, heating the nickel iron glycerate ball powder at a heating rate of lower than 1.5° C./min to not less than 350° C. for performing calcination to obtain the core-shell nickel ferrite. The preparation method of the nickel ferrite@C material includes: performing a phenolic resin condensation reaction on the core-shell nickel ferrite, resorcinol and formaldehyde to obtain a phenolic resin (RF) coated core-shell nickel ferrite@RF composite material; and in an inert atmosphere, calcining and carbonizing the nickel ferrite@RF composite material to obtain the nickel ferrite@C material.

The present disclosure provides core-shell nickel ferrite, a nickel ferrite@C material and preparation methods and application thereof. The preparation method of the core-shell nickel ferrite includes: preparing nickel iron glycerate ball powder by a solvothermal method; and under an air condition, heating the nickel iron glycerate ball powder at a heating rate of lower than 1.5° C./min to not less than 350° C. for performing calcination to obtain the core-shell nickel ferrite. The preparation method of the nickel ferrite@C material includes: performing a phenolic resin condensation reaction on the core-shell nickel ferrite, resorcinol and formaldehyde to obtain a phenolic resin (RF) coated core-shell nickel ferrite@RF composite material; and in an inert atmosphere, calcining and carbonizing the nickel ferrite@RF composite material to obtain the nickel ferrite@C material.

A positive electrode slurry including a positive electrode material mixture and a dispersion medium for dispersing the positive electrode material mixture. The positive electrode material mixture contains a positive electrode active material, an electrically conductive agent, a binder, and an additive. The additive includes a compound intramolecularly having a polyether group and an acidic group.

Methods and systems are provided for a blend of cathode active materials. In one example, the blend of cathode active materials provides a high power battery with low direct current resistance while improving lithium ion cell safety performance. Methods and systems are further provided for fabricating the cathode active material blend and a battery including the blend.

Provided is a negative electrode active material for a lithium secondary battery which includes: a silicon-silicon oxide-magnesium silicate composite comprising a silicon oxide (SiO.sub.x, 0<x≤2) matrix; and silicon (Si) crystal grains, MgSiO.sub.3 crystal grains and Mg.sub.2SiO.sub.4 crystal grains present in the silicon oxide matrix, wherein the MgSiO.sub.3 crystal grains have a crystal size of 5-30 nm and the Mg.sub.2SiO.sub.4 crystal grains have a crystal size of 20-100 nm in the silicon-silicon oxide-magnesium silicate composite, and the content ratio of MgSiO.sub.3 crystal grains to Mg.sub.2SiO.sub.4 crystal grains is 2:1-1:1 on the weight basis. A method for preparing the negative electrode active material for a lithium secondary battery is also provided.

A method of manufacturing a battery cell includes forming an electrode and coating the electrode with a n-mer solution. The n-mer coated electrode is treated by heat, ultraviolet, or cross linking agents to polymerize the n-mer and form an ion exchange material that covers at least some of the electrode.

A method of manufacturing a battery cell includes forming an electrode and coating the electrode with a n-mer solution. The n-mer coated electrode is treated by heat, ultraviolet, or cross linking agents to polymerize the n-mer and form an ion exchange material that covers at least some of the electrode.

Provided is an alkali metal-sulfur battery, comprising: (a) an anode; (b) a cathode having (i) a cathode active material slurry comprising a cathode active material dispersed in an electrolyte and (ii) a conductive porous structure acting as a 3D cathode current collector having at least 70% by volume of pores and wherein cathode active material slurry is disposed in pores of the conductive porous structure, wherein the cathode active material is selected from sulfur, lithium polysulfide, sodium polysulfide, sulfur-polymer composite, sulfur-carbon composite, sulfur-graphene composite, or a combination thereof; and (c) a separator disposed between the anode and the cathode; wherein the cathode thickness-to-cathode current collector thickness ratio is from 0.8/1 to 1/0.8, and/or the cathode active material constitutes an electrode active material loading greater than 15 mg/cm.sup.2, and the 3D porous cathode current collector has a thickness no less than 200 μm (preferably thicker than 500 μm).

Provided is an alkali metal-sulfur battery, comprising: (a) an anode; (b) a cathode having (i) a cathode active material slurry comprising a cathode active material dispersed in an electrolyte and (ii) a conductive porous structure acting as a 3D cathode current collector having at least 70% by volume of pores and wherein cathode active material slurry is disposed in pores of the conductive porous structure, wherein the cathode active material is selected from sulfur, lithium polysulfide, sodium polysulfide, sulfur-polymer composite, sulfur-carbon composite, sulfur-graphene composite, or a combination thereof; and (c) a separator disposed between the anode and the cathode; wherein the cathode thickness-to-cathode current collector thickness ratio is from 0.8/1 to 1/0.8, and/or the cathode active material constitutes an electrode active material loading greater than 15 mg/cm.sup.2, and the 3D porous cathode current collector has a thickness no less than 200 μm (preferably thicker than 500 μm).